ByteBlockReader.index.page.start: def of mylsm-lsm-store@0.6.0.1
Import: import mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend as ByteBlockReader
Lines 1643-1654 of mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend: https://jend.leeeet.dev/read.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&start_line=1643&end_line=1654

import Base
import mylsm-lsm-store@0.6.0.1/src/scan/BlockIndexPolicy.bend as BlockIndexPolicy
import mylsm-lsm-store@0.6.0.1/src/hub_sha/sha256.bend as SHA

def index.page.start(file: File, state: State) -> IO(Result<&1, &1, U32 & String, Step>):
  match state:
    case State{+size, _, +index_offset, _, +total, _, _, _, root_hash,
        index_hash, _, _}:
      +remaining = Nat.sub(size, Nat.add(index_offset, 44n))
      +index_length = U32.from_nat(remaining)
      +page_bytes = BlockIndexPolicy.max_bytes()
      +pages = Nat.div(Nat.add(remaining, Nat.sub(page_bytes, 1n)), page_bytes)
      +fuel = Nat.add(Nat.mul(3n, pages), 1n)
      index.page.loop(fuel, IndexPageNeed{file,
        IndexMeta{total, index_length, index_hash}, index_offset, remaining,
        SHA.stream.initial(), root_hash})

Uses (18):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=File
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=IO
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.div
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.mul
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.from_nat
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/hub_sha/sha256.bend&name=stream.initial
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/BlockIndexPolicy.bend&name=max_bytes
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&name=IndexMeta
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&name=IndexPageState
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&name=State
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&name=Step
  https://jend.leeeet.dev/definition.txt?path=mylsm-lsm-store@0.6.0.1/src/scan/ByteBlockReader.bend&name=index.page.loop